Rapidly progressive subacute sclerosing panencephalitis presenting with acute loss of vision.

A 10-year-old male presented with vision loss and behavioral changes. He had midpoint pupils with no reaction to light and normal funduscopic examination. Cranial magnetic resonance imaging revealed bilateral cortical lesions at parieto-occipital lobes. Elevated measles antibody titers in the cerebrospinal fluid confirmed the diagnosis of subacute sclerosing panencephalitis. Despite oral inosiplex and supportive care, patient developed generalized seizures with frequent myoclonic jerks and rapidly progressed into coma. Cortical blindness in subacute sclerosing panencephalitis can be an early indicator for fulminant course.